1. Field of the Invention
The present invention relates to an image capturing lens for forming an optical image of a subject on an image sensor, such as a CCD (Charge Coupled Device), CMOS (Complementary Metal Oxide Semiconductor), or the like, and an image capturing apparatus having the image capturing lens mounted thereon to perform image capturing, such as a digital still camera, camera-equipped cell phone, personal digital assistance (PDA), smartphone, tablet terminal, portable video game player, or the like.
2. Description of the Related Art
Recently, along with the spread of personal computers to homes and the like, digital still cameras capable of inputting image information obtained by imaging a landscape, a person, or the like to a personal computer have been spreading rapidly. In addition, more and more cell phones, smartphones, or tablet terminals have built-in camera modules for inputting images. Such devices with image capturing capabilities employ image sensors such as CCDs, CMOSs, and the like. Recently, these types of image sensors have been downsized greatly and, consequently, image capturing devices as a whole and image capturing lenses to be mounted on such devices have also been required to have more compact sizes. At the same time, the pixel count of image sensors has been increasing, thereby causing a growing demand for improvement of image capturing lenses in resolution and performance. For example, performance corresponding to high pixel counts, such as more than 2 mega pixels (MP), more preferably more than 5 MP, and further preferably more than 8 MP, is demanded.
For such demands, it is conceivable to employ a five-lens configuration having a relatively large number of lenses in order, for example, to achieve the reduction in overall length and the improvement in resolution (refer to Japanese Unexamined Patent Publication No. 2007-264180, Japanese Unexamined Patent Publication No. 2007-298572, Japanese Unexamined Patent Publication No. 2010-256608, Japanese Unexamined Patent Publication No. 2011-85733, Chinese Utility Model No. 202110325, and U.S. Patent Application No. 2012/087019).